Gavino C. Trono, Jr.
Professor
Marine Science Institute, College of Science
University of the Philippines
Diliman, Quezon City
Philippines

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Several species and varieties of Caulerpa
may be utilized as food in the form of fresh
vegetables. These are mainly produced
through gathering of natural stocks. Only
C. lentillifera is commercially cultivated in
ponds in the Philippines. The culture of
this species started in the early 1950s in
the island of Mactan, province of Cebu,
Central Visayas. The accidental introduction
of C. lentillifera with some other seaweed
species to fishponds as fish food initiated
its formal cultivation. The high demand for
this alga in the local markets in metropolitan
Cebu was a major factor contributing
to the success of its commercial production.
The species is preferred because of its delicate,
light taste, soft and succulent texture. It is
also a fast growing species.

The pond culture of C. lentillifera was started
by a fishfarmer in 1952 utilizing his fishponds
with milkfish and shrimp. At the
beginning, Caulerpa was a secondary crop
to fish and shrimp but later, because of the
marginal production of fish and shrimp
compared to the high production of Caulerpa,
the farmer shifted to Caulerpa as his major
crop and milkfish and shrimp became secondary
crops. Interviews made among farmers
revealed that some 400 hectares of ponds
are presently used for the culture of Caulerpa.
Although the commercial culture of Caulerpa
in ponds started more than two decades ago,
it has not been successfully transferred to
other parts of the Philippines as yet, with
the exception of the pond and open reef
culture in Calatagan, Batangas, introduced
by the author in early 1980s, so that the bulk
of the fresh supply of Caulerpa in Metro
Manila and some bigger towns in Central
Luzon still comes from Mactan, Cebu.
Although local consumption statistics are
not available, it is probably safe to assume
that several tons of Caulerpa are transported
to Metro Manila from Mactan, Cebu every
month. This seaweed is always available
in the local markets any day of the week.
The statistics of the Bureau of Fisheries and
Aquatic Resources showed that in 1982 some
827 tons of Caulerpa were exported to Japan
and Denmark in fresh, brine-cured and salted
form.

The present cultivation utilizes the traditional
brackishwater ponds. However,
results of recent studies (Trono, 1987)
have shown that water management is a
primary factor in the productivity of Caulerpa,
the culture of which would require a flowthrough
system to facilitate water exchange.
Thus, some modification of the traditional
ponds such as the introduction of water
control gates have to be made. Unlike pond
culture of fish where water exchange is relatively
infrequent (e.g., once a week or a
fortnight) pond culture of Caulerpa requires
more frequent water exchange in order to
maintain the necessary level of nutrients
required for growth and development.
Some of the more progressive farmers in
Mactan had through experiences, learned
the importance of proper water management
and achieved higher production
through the introduction of some form of
a flow-through system by providing both
entry and exit gates for each pond compartment.

The genus Caulerpa belongs to the Family
Caulerpaceae, Order Caulerpales in the Division
Chlorophyta. All representatives of this
genus have thalli consisting of long branching
horizontal stolon which gives rise to
rhizoids at its ventral side for attachment
and many simple or branched erect portions
which are green in color. The erect branches
come in various forms depending on the
species, e.g., strap-shaped or blade-like with
or without teeth or spines at their margins,
or, these bear short determinate laterals
(ramuli) of various forms, e.g., coarse teeth,
fine cylindrical branchlets (pinnules), clavate,
globose or peltate branchlets.

The members of this genus are large
coenocytes, i.e., the thallus is a single cell,
large continuous tube without cross walls
(aseptate). The algal body is strengthened
by the structures known as internal trabeculae,
the extensions of the inner wall. Information
available on reproduction is based
mainly on the results of studies of a few
species. The alga is diploid (diplontic) and
no alternation of generation has been
recorded. Gamete (biflagellated) formation
in undifferentiated gametangia is preceded
by meiosis. The gametes are liberated
through superficial papillate structures.

There are more than 30 species and varieties
of Caulerpa reported in the Philippines.
Among the more common species (Trono
and Fortes, 1988) are C. racemosa (Figure 1),
C. lentillifera (Figure 2), C. brachypus (Figure 3),
C. sertularioides (Figure 4), C. serrulata (Figures
5a-5b); C. taxifolia (Figure 6), C. peltata,
C. urvilliana and C. cupressoides. Caulerpa
racemosa (Figure 7) and C. lentillifera are
gathered from wild stocks and sold in
markets. Only C. lentillifera is presently
cultured in ponds.

The genus Caulerpa is mainly distributed
in the tropics but also forms a major component
of the seaweed flora in Australian
temperate waters.

The development of a new area into Caulerpa
ponds consists of several stages, namely; site
selection, pond construction, planting of
the ponds, maintenance of the culture,
harvest and post-harvest activities. Fishponds
with marginal production are usually
preferred because initial investment for their
conversion to Caulerpa ponds is low and
usually the location of these unproductive
fishponds generally fits the ecological
requirements of Caulerpa culture, that is,
they are far from sources of freshwater
and pollution sources.

The success in the culture of Caulerpa
depends primarily on the selection of a good
site. The following ecological factors have
to be considered when selecting sites for
pond culture of Caulerpa.

The site must be far from sources of
freshwater such as rivers and streams.
Caulerpa is a purely marine stenohaline alga
and will die even in slightly brackish seawater.
The salinity should not be lower than
30 ppt.

The elevation of the pond bottom must
be at or just a little above the zero tidal level.
This is necessary in order to enhance proper
water management in the ponds. Frequent
water change is necessary for the growth
and development of Caulerpa.

The site must be protected from the
destructive effects of wind and waves. A
buffer zone of mangroves and/or coral reef
is necessary.

The substrate must be loamy-muddy.
However, very deep, soft mud must be
avoided.

Sites with acidic soil should be avoided.
Caulerpa will not grow in areas characterized
by low pH.

The area must be near the source of
unpolluted seawater supply. Caulerpa is
consumed fresh, thus it must be grown in
areas free from both domestic and industrial
pollution. Bacterial contamination of the
crop should be avoided. Caulerpa may also
absorb pollutants such as heavy metals and
toxic chemicals which it can accumulate with
deleterious effects to the consumers.

Existing saltwater ponds can be used
for Caulerpa culture. Some farmers stock
milkfish in Caulerpa ponds as a secondary crop.

The maintenance of good water quality
necessary for good growth of Caulerpa
through proper water management is dependent
on the proper design of the ponds. The
traditional layout of ponds for milkfish
and shrimp production does not provide the
necessary water exchange required in Caulerpa
culture.

Caulerpa ponds may be divided into compartments
of 0.10 to 0.25 hectare and should
incorporate a flow-through design; each
of the compartments should be provided
with individual entrance and exit gates
positioned in such a way that the water
could easily be changed and circulated
during the draining and flooding process.
The flow-through design is important to
facilitate frequent and complete water
change necessary in maintaining high nutrient
level in the seawater required by the
seaweed for rapid growth and development.
Peripheral or diversion canal may also have
to be provided to divert runoff water from
the ponds during rains to avoid drastic
lowering of salinity in the ponds which is
detrimental to the crop (Figure 8).

The ponds should be drained to a depth
of 0.3 meters to facilitate planting. During
the early development of the culture,
broadcasting was used to “seed” the ponds
with Caulerpa cuttings. However, this technique
was found to be inefficient because
the “seeds” were not uniformly distributed
on the pond bottom and resulted in the
uneven growth of the crop.

Planting is done by burying into the mud
one end of a handful of Caulerpa cuttings at
about one meter interval. Uniform planting
is facilitated with the use of lines as guide
or the planted spots are marked by pieces
of bamboo. After planting, the ponds should
be flooded to a depth of about 0.5 to 0.8 m.
Flooding should be done slowly to prevent
the newly planted cuttings from being
uprooted and carried away by the current.
The newly planted ponds must be inspected
a day or so after planting and the unplanted
areas should be planted to ensure uniform
growth. The pond water should be changed
only several days after planting to make
sure that the cuttings are already well rooted
and could not be carried away by water
currents.

An initial stocking rate of 1 000 kg per
hectare under favourable weather conditions
can produce a good crop in about two to three
months.

Proper water management is also a key
factor in the successful pond culture of
Caulerpa. Ideally, the pond water must be
changed every three to four days at the start
of the growing period in order to avoid strong
water currents which may uproot the seedlings.
The frequency of water changes
should be increased to every other day at
about the third week after planting especially
when the plants start to form a thick growth
on the pond bottom. Frequent water exchanges
provide fresh supply of nutrients
for the normal growth and development of
Caulerpa, thus, it will eliminate the need
for fertilizer application.

In general the water in the ponds must
be maintained at a depth where the Caulerpa
is visible from the surface of the water.
Thus, the depth of the water in the pond
would vary depending on the transparency
of the pond water to provide enough light
for the photosynthetic needs of the plants.
However, adjustments in water depth should
be made to avoid perimeter dikes from collapsing
during spring tides when the tidal
amplitudes are extreme. During rainy days
the pond water should also be maintained
at a slightly greater depth to reduce the
possibility of a dilution below 30 ppt. Caulerpa
will die when the salinity goes below this
level and the entire crop may be lost. After
heavy rains the pond water should be immediately
drained and replaced by fresh seawater
to ensure that the salinity is maintained
at or above 30 ppt.

Fertilization may not be necessary as long
as frequent water exchange can be made.
However, fertilizer has to be applied especially
one or two weeks before the harvest,
when a large crop has already been produced
and when the plants appear to be pale in color
(that is light green or yellowish). The sufficient
rate of fertilization is about 16 kg per
hectare. Nitrogeneous fertilizers have produced
very good results. The plants regain
their healthy green color a few days after
application. The fertilizer may be broadcasted,
but past experience had shown that
wrapping the fertilizer in many layers of
gunny or plastic sacks and suspending these
in strategic places in the pond at a level where
the bags are just about half submerged in
water, produces very good results. The fertilizer
should be applied right after water
in the pond has been changed. The pond
water should not be changed for several
days after the fertilizer has been applied.

Weeding is an important activity which
should be done regularly to remove other
seaweed species and associated organisms
growing in the pond. Weeds compete with
Caulerpa for space, light and nutrients. The
weeds and the associated organisms should
be removed before they take over as dominants.
The presence of the weeds results
in decreased production and low quality of
the product and adds extra labor cost to sort
them out before the product is sold in the
market.

The dikes and gates of the ponds must be
continuously maintained to effect efficient
water management. This is especially critical
during the monsoon season when strict and
efficient water management is required to
avoid extreme dilutions due to heavy rains.

Depending on the growth rate of the plants
the crop may be harvested two months after
the initial planting, when the plants had
already formed a relatively uniform carpet
on the pond bottom. The plants at this stage
are of high market quality, light grass-green
in color, soft and succulent in texture. Older
plants though high in biomass are of lower
quality because they are tougher in texture
and their basal portions are pale or colorless.
The paling of the basal portions of the fronds
are caused by self-shading when the plants
became older and form very thick carpet.

Figure 9. Pond-grown Caulerpa lentillifera

Figure 10. Harvesting of pond-grown
Caulerpa lentillifera

Harvesting is done by uprooting the plants
(Figures 9–10) from the muddy pond
bottom. More crops can be produced during
a growing season if partial harvesting is
done leaving a sizeable amount of
20–25 percent of the crop in the pond to
serve as seedstock for the next crop.
Harvesting should be done in such a way
that the leftover of the crop is more or
less uniformly distributed in the ponds.
Large vacant areas of the pond bottom
should be replanted to ensure uniform
crop stand. This practice has drastically
reduced production costs by savings made
in labor costs for replanting. The sizeable
amount of seedstock left in the pond
also results in a much shorter growing
period and the farmers in Mactan, Cebu
claim they can harvest every two weeks
after the first harvest during the optimal
growing season (dry season). Studies
have shown that the algae could triple its
initial weight after two months (Trono and
Denila, 1987).

Harvested seaweeds are thoroughly
washed in seawater to remove the mud
and other debris. They are then sorted,
unsuitable thalli and other seaweed species
are removed. The clean seaweed is placed
in bamboo baskets lined with banana leaves
or other seaweeds such as Sargassum. The
baskets are filled with clean seaweeds,
then topped with leaves or Sargassum and
finally covered with plastic sack which is
secured by lacing its margin to the basket.
The baskets (Figure 11) are placed under
the shade where they are allowed to drip
before transporting them to the market.
The product can stay fresh for four to five
days.

Caulerpa destined for export to other
countries (such as Japan) is exported as a
fresh product or in brine-cured or salted
form. The seaweed is first thoroughly
washed several times in seawater. Then
thalli of good quality are selected. The clean
seaweed is first completely drained of water,
packed in styrofoam boxes provided with
aeration holes on the upper side or cover of
the box, taped and sent to its destination by
air cargo. A large portion of Caulerpa exported
to other countries is either brine-cured or
salted. The latter two forms can be kept for
longer periods and may be transported by
surface cargo.

Based on experimental work on pond
culture of Caulerpa conducted for a one
year cycle at varying amounts of seed stock,
the estimate annual production per ha of
pond is optimum at an initial seeding of
100 g/m2 as shown in Table 1.

Table 1. Estimate production of Caulerpa lentillifera two months after
planting based on the biomass production (wet weight)
studies from April 1981 to May 19821

The estimate economics of production
is encouraging as shown in Table 2. An
annual estimate farm income of 78 000.00
in the first year is highly profitable considering
a farm gate wholesale price of
8.00/kg. This is equivalent to a ratio of
net income to capital at the rate of 146 percent
which is rather very optimistic. On
the other hand, this is a possibility if
pond management is good and the pond conditions
are kept favourably well for the
growth of the algae.

Although several species of agarophytes
belonging to the genera Gelidium, Pterocladia
and Gracilaria have been reported to be commercially
produced through some form of
farming in several countries such as Japan,
China, Republic of Korea, Vietnam, India
and the Philippines, it is in Taiwan where
the production of Gracilaria through pond
culture has achieved a high degree of
success. An average of 12 000 tons of
dried Gracilaria was produced in Taiwan
during the past few years (Chiang, 1981).
It is a very important raw material for the
manufacture of agar which finds wide
variety of uses in the food, pharmaceutical
and several other industries.

Out of the several species presently used
for culture in some countries (e.g., Gracilaria
chorda, G. edulis, G. “verrucosa”, G. lichenoides,
G. compressa and G. gigas). G. “verrucosa” is the
most popular due to its ability to adapt to a
wide range of ecological conditions, its higher
production rates and better gel quality. The
culture of Gracilaria started in 1962 in southwestern
Taiwan. Production in ponds is
primarily influenced by three ecological
factors, namely; salinity, light and temperature.
High production is recorded during
the months characterized by higher temperatures
and growth is slow during winter.
High light intensity exerts adverse effects
on the growth, therefore, control of light
conditions is practiced by adjusting the water
depth in the ponds. Salinity of 20 to 24 ppt
appears to be optimal for growth. The
increase in salinity during the summer
months is controlled by the addition of
freshwater, thus farms need to be located
near freshwater sources.

The genus Gracilaria belongs to the Family
Gracilariaceae, Order Gigartinales in the Division
Rhodophyta. It is a large genus represented
by more than a hundred species widely
distributed in the tropical and temperate
waters of the world.

The thalli of Gracilaria are generally fleshy
and vary widely in form from flattened to
foliose forms or mainly branching forms,
the branches being compressed to cylindrical
in transverse section. The tissue is mainly
pseudo-parenchymatous.

Figure 1. Gracilaria eucheumoides

More than 17 species have been recorded
in the Philippines. However, only G. eucheumoides
(Figure 1), G. arcuata (Figure 2), G. coronopifolia
(Figure 3), G. salicornia (Figure 4),
G. “verrucosa” (Figure 5) and G. gigas (Figure 6)
are well documented. Of these species only
G. “verrucosa” and Gracilaria sp. 2 (Trono, et al.,
1983) are presently gathered from wild
stocks and utilized in the local manufacture
of agar although the other species have been
reported to have good quality agar.

The genus Gracilaria is characterized by
the alternation of three somatic generations,
the sporophyte, the gametophyte and the
carposporophyte stages. The last stage is
microscopic and is parasitic on the female
gametophytes, thus the gametophytic and
tetrasporophytic stages are the macroscopic
stages used as planting materials in the pond
culture. The tetrasporangia are of the zonate
type. Although the reproductive potential
of Gracilaria through spores is high, vegetative
propagation by cuttings is presently
used in the pond culture because of the very
high regenerative capacity of the plant and
the simplicity of the method. However,
“hatchery produced” seedlings from spores
have been demonstrated to be superior in
the open field culture of Gracilaria.

Figure 2. Gracilaria arcuata

This manual is designed to provide the
prospective farmer guidelines for a successful
pond culture of Gracilaria.

The success in pond culture of Gracilaria
is highly dependent on the selection of
appropriate site. The following criteria are
recommended in the selection of sites.

The prospective farmer should choose
a site located and accessible to sources of
seawater and freshwater supply. Gracilaria
is a euryhaline alga and would grow very
well in a wide range of salinity. Brackish
water with a salinity range of 20 ppt to
28 ppt favors growth although salinity
of 25 ppt is optimum. Salinity rises during
sunny months due to evaporation reaching
values as high as 35 ppt which depresses
growth or cause the death of the plants.
It is, therefore, important that salinity
should be lowered to its normal range of
tolerance by adding freshwater into the
ponds. Salinity may also drop to very low
levels beyond the minimum limits for
heavy rains. Very low salinity is also detrimental
to the plants and may cause mass
mortality. The salinity level should be raised
to its optimal range by adding seawater.

Thus, the maintenance of optimal salinity
conditions in the ponds requires the readily
available freshwater and seawater supply.

Figure 3. Gracilaria coronopifolia

Figure 4. Gracilaria salicornia

Figure 5. Gracilaria “verrucosa”

Figure 6. Gracilaria gigas

The pond site should also be protected
from strong winds or waves. Strong winds
produce waves which tend to transport
Gracilaria towards the leeward portion of
the ponds. The formation of thick heaps of
Gracilaria has also adverse effects on growth
due to shading. On the other hand, strong
waves can wash out the dikes and cause tremendous
loss and damage to the pond and
crop.

The pond bottom should be at or just
a few centimeters above the zero tide line.
The maintenance of optimum salinity levels
in ponds is a major factor in the production
of good crops. The ease and efficiency in
water management is highly influenced by
the level of the pond bottom in relation to
the tidal changes. Frequent water changes
is very necessary to maintain the nutrient
and salinity levels in ponds favourable to
the growth of Gracilaria.

The pH of the water in ponds should
be slightly alkaline from seven to nine and
a pH range of 8.2–8.7 is optimum for growth.
Sites with low pH (acidic) should be avoided.
Frequent water change may also help in the
maintenance of optimum pH levels in ponds.

The pond bottom should be sandy loam.
Ponds with very soft muddy bottom should
be avoided. Cuttings of Gracilaria will easily
sink in mud and die.

Existing brackishwater ponds are
usually used for Gracilaria farming as
the seaweed could be grown with crabs and
shrimps.

The average size of ponds used for the
culture of Gracilaria is about one hectare or
smaller. Smaller ponds are easier to manage
than larger ones because in large ponds
Gracilaria tend to accumulate at one side
due to the influence of wind-induced waves.
Pond management is also easier when Gracilaria
is polycultured with shrimp and/or
crab. Provision of entrance and exit gates
also facilitate proper water management.

The depth of the ponds vary from 50 to
80 cm. The bottom generally is of clayey
loam, or sandy loam. It was observed that
Gracilaria easily gets buried in the bottom
of the pond due to the effect of wind. This
problem, however, could be resolved by
increasing the depth of the water during
windy periods. In larger ponds, wind breaks
consisting of bamboo slots are installed perpendicular
to the direction of the wind to
prevent the seaweed from being transported
to one side of the pond.

The following method is generally followed
in the pond culture of Gracilaria.

The ponds should be drained and dried
for several days after which water is introduced.
Healthy stocks of Gracilaria are
selected as planting materials. These are
generally characterized by their elastic feel
to touch, reddish brown color, brittle texture,
stout and well-branched thalli and are free
of dirt and extraneous materials. The planting
materials are transported from its source
to the pond site early in the morning to
prevent its exposure to the sun. During
long distance transport, the materials should
be frequently sprinkled with seawater and
perforated bamboo or plastic pipes are
inserted into the bottom of the heap to provide
aeration. The plants must immediately
be placed in water in the pond upon arrival.
The planting material should be cut into
pieces and should be broadcasted uniformly
on the bottom of the pond. Stocking rate is
5 000 to 6 000 kg per hectare although lesser
amounts may be used. Cropping season
usually starts during warm summer months
of March or April.

The water should be maintained at a depth
where the surface is approximately 30 to
40 cm above the heap of the algae. However,
the depth should be increased to 60 to 80 over
the algae during the warm summer months
to prevent a significant rise in the water
temperature. Water depth should be
increased during the cold months to prevent
water temperature from dropping to very
low levels which may be lethal to Gracilaria.
Water temperature range of 20–25 (29)°C
or slightly higher should be maintained in
ponds for maximum growth.

Frequent change of water is necessary
to maintain the optimum temperature of
water in the ponds. The water is changed
every two to three days. About 50 to
75 percent of the “old” pond water
should be drained and replaced with
fresh seawater.

Fertilization with either organic or
inorganic fertilizers may be done to enhance
the growth of Gracilaria. Weekly application
of 3 kg of urea per hectare should be sufficient.
Fermented pig manure may be applied
at a rate of 160 to 180 kg per hectare two
to three days after the pond water has been
changed. Pond water should not be changed
for several days after fertilization.

The harvesting may be done two to three
months after seeding depending on the
growth of the crop. The crop may be harvested
manually or by using scoop nets every
10 to 40 days. The frequency of harvests
should be primarily dictated by the market
price, amount of harvestable biomass and
the season. In subtropical and temperate
areas, the low temperature during winter
is inimical to the growth of the crop.

The harvest should be thoroughly washed
in pond water to remove the silt, sand,
pieces of shells and other extraneous materials
such as snails and other algae. The
clean Gracilaria is spread uniformly on
bamboo screens or plastic sheets for drying.
An average wet to dry ratio of 7:1 is generally
attained.

Standards set by the Bureau of Standards
in Taiwan for the export of dried Gracilaria
require that the product should not contain
more than 1 percent of mud and sand, not
more than 1 percent shells and not more
than 18 percent other seaweed species.
Moisture content should not exceed 20 percent
(T.P. Chen, 1976).

Dried Gracilaria is packed into bales of
100 kg weight for export or sold to local
processing plants. Production of 10 to
12 metric tons of dried Gracilaria is attained
in a hectare of pond in Taiwan. More recently
fresh Gracilaria crops are utilized as feed in
the culture of abalone.

Gracilaria may be polycultured with shrimp
(Penaeus monodon) and/or crab (Scylla serrata)
as is being done in southwestern Taiwan.
Stocking materials for a hectare of farm
consist of 4 000 to 5 000 kg of Gracilaria,
5 000 to 10 000 crabs and 10 000 to 20 000
shrimp fry. Crushed trash fish and snails
are generally used as feed for the crabs.
Crabs are harvested after three months and
the shrimps after four to seven months.
Survival rates as high as 80 percent for crabs
and 80 to 90 percent for shrimps have been
documented making this polyculture one
of the most profitable aquaculture methods
in Taiwan. The net income from polyculture
has been proven to be three times as much
as from monoculture.

The presence of other seaweed species
(weeds) in the ponds mixed with Gracilaria
is one of the problems in the culture of this
seaweed. The weed species have to be
removed or weeded out to prevent these
from becoming dominant. The weeds compete
with Gracilaria for nutrients and light.
These also lower the quality (value) of the
crop. Epiphytes, other smaller algae growing
on Gracilaria, are other problems which may
be solved by the introduction of grazers in
the ponds. Tilapia has been found to be
effective in the control of epiphytes. A
low density of milkfish or tilapia may be
stocked in Gracilaria ponds to control epiphytes
and other green algae.

The culture of this alga in the Philippines
used to be an extensive method applied by
milkfish farmers primarily for the food of
the milkfish. During the period of abundance
of Gracilaria in Manila Bay, fishpond
operators collect them for stocking in milkfish
ponds. There has been no documentation
of this practice but the use of the algae
as milkfish feed has been reported. Unfortunately,
there was no economic evaluation
of the practice. The Philippine experience
on the farming of this seaweed, although
not for its agar but for milkfish feed was,
however, short lived due to the heavy pollution
of Manila Bay. Milkfish ponds generally
rely on benthic algae or “lab-lab” by organic
and inorganic fertilization of ponds.

The economics of Gracilaria farming
in this manual is, therefore, based on
Taiwanese experience where the practice is
more intensive. Table 1 summarizes the
costs and earnings per hectare of Gracilaria
farming.

ASEAN/SF/88/GEN/7 Report on the training/study tour of pelagic fishing with the use of “payaw” held
in Manila, Philippines, 16 May-4 June 1988. Manila, ASEAN/UNDP/FAO Regional Small-Scale
Coastal Fisheries Development Project, 1988. (In preparation).

ASEAN/SF/88/GEN/8 Report of the workshop on artificial reefs development and management held
in Penang, Malaysia, 13–16 September 1988. Manila, ASEAN/UNDP/FAO Regional Small-Scale
Coastal Fisheries Development Project, 1988. (In preparation).

ASEAN/SF/85/Tech. 1 Rabanal, H. R. and V. Soesanto. The world fishery and culture of Macrobrachium
and related prawn species. Contributed to the National Conference on Prawn Technology, sponsored
by the Philippine Fishfarmer's Technical Assistance Foundation, Inc., Manila, Philippines,
27–28 November 1985. 16p.

ASEAN/SF/86/Tech. 2 Rabanal, H. R. and V. Soesanto. Commercial species of shrimps and prawns, their
sources and export markets. Contributed to the Seminar on Quality Control in the Production,
Processing and Marketing of Frozen Shrimps for Export, sponsored by Food Research Department,
Food Terminal Incorporated, Taguig, Metro Manila, Philippines, 29–31 July 1986. 64p.

ASEAN/SF/86/Tech. 3 Rabanal, H. R. Status and prospects of Shrimp farming in the Philippines. Contributed
to the Monthly Seminar Series on Timely and Related Fisheries Issues, sponsored by the Philippine
Council for Agriculture and Resources Research and Development, (PCARRD), Los Banos, Laguna,
Philippines, 5 November 1986. 24p.

ASEAN/SF/87/Tech. 4 Delmendo, M. N. Fishery administration and policy in the Philippines: Past and
present. Contributed to the National Conference on Fisheries Policy and Planning, Baguio City,
Philippines, 16–20 March 1987. 35p.

ASEAN/SF/86/Tech. 5 Delmendo, M. N. Milkfish culture in pens: An assessment of its contribution to
overall fishery production of Laguna de Bay. Paper read in the Seminar on the occasion of the Fish
Conservation Week, BFAR, October 1987. 17p.